Venezuela's Vice President Tareck El Aissami speaks during a meeting with ministers in Caracas

CARACAS (Reuters) - The Venezuela government will start auctioning its new petro cryptocurrency to private companies via its Dicom foreign exchange platform in a few weeks, Vice President Tareck El Aissami said on Tuesday.

The OPEC country last month began selling the new digital token, which President Nicolas Maduro has said will be backed by oil reserves, in a private sale to investors. Maduro says the petro will help skirt U.S. financial sanctions.

Opposition critics call the petro an illegal debt issue, and the U.S. Treasury Department has warned that it may violate sanctions and thus constitutes a legal risk for investors.

"The petro is going to be auctioned on Dicom," El Aissami said in a meeting with businessmen broadcast on state television, adding that companies will be able to use petros to pay for imports of raw materials.

"The petro is going to be our powerful international currency, above the dollar."

It is not immediately evident if and how the petro can function as foreign currency or how it would help Venezuelan businesses with international commerce transactions.

Foreign companies are unlikely to accept it as payment given the legal doubts surrounding it, and few investors have publicly announced having purchased it.

El Aissami also called on local banks to buy the petro at a discount during the preliminary phase, which ends on March 20.

During this phase, petros can be acquired with "dollars, euros or any other currency," he said, and may be held by banks as assets on their balance sheets.